Abstract

The effects of lanthanum incorporation into dielectrics were studied using first-principles total energy calculations. The author’s computational result clearly showed that the formation energy of a neutral oxygen vacancy in the vicinity of substitutional La atoms at Hf sites is larger than that in pure , indicating that the concentration of ’s is drastically reduced by La incorporation. This effect is understood to be caused by the decrease in the local dielectric constant around La atoms due to the strong ionic character of the La–O bond compared to the Hf–O bond.

Received 29 July 2007Accepted 03 September 2007Published online 25 September 2007

Acknowledgments:

This work was partly supported by the High- Network in cooperation with academic, industry, and governmental institutes, and a Grant-in-Aid for Scientific Research No. 18360017 from MEXT. One of the authors (N.U.) would like to thank Prof. T. Nakayama, Dr. M. Otani, and Dr. K. Kamiya for their useful advice.